add -bounds-checking-multiple-traps option to make one trap BB per check
disabled by default for now; we can discusse the default value (& name) later
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157777 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/BoundsChecking.cpp b/lib/Transforms/Scalar/BoundsChecking.cpp
index 738b1f2..2ed65eb 100644
--- a/lib/Transforms/Scalar/BoundsChecking.cpp
+++ b/lib/Transforms/Scalar/BoundsChecking.cpp
@@ -20,6 +20,7 @@
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpander.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
+#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/InstIterator.h"
#include "llvm/Support/IRBuilder.h"
@@ -35,6 +36,9 @@
#include "llvm/Pass.h"
using namespace llvm;
+static cl::opt<bool> ManyTrapBB("bounds-checking-multiple-traps",
+ cl::desc("Use one trap block per assertion"));
+
STATISTIC(ChecksAdded, "Bounds checks added");
STATISTIC(ChecksSkipped, "Bounds checks skipped");
STATISTIC(ChecksUnable, "Bounds checks unable to add");
@@ -98,7 +102,7 @@
/// getTrapBB - create a basic block that traps. All overflowing conditions
/// branch to this block. There's only one trap block per function.
BasicBlock *BoundsChecking::getTrapBB() {
- if (TrapBB)
+ if (TrapBB && !ManyTrapBB)
return TrapBB;
BasicBlock::iterator PrevInsertPoint = Builder->GetInsertPoint();